Introduction 

Rickets: Defective bone mineralization in children before epiphyseal fusion

Osteomalacia: Defective bone mineralization in adults with fused epiphyses

-The most common cause of osteomalacia: Vitamin D deficiency 

-Drug-induced osteomalacia caused by phenytoin, carbamazepine, valproate, phenobarbital 

Calcipenic rickets occurs in 4 forms:

Nutritional rickets 

Vitamin D-dependent rickets type I

Hereditary vitamin D resistant rickets

Defects in vitamin D metabolism 

Hypophosphatemic rickets occurs in 2 forms: 

-nutritional hypophosphatemic rickets 

-X-linked hypophosphatemic rickets 

Symptoms & Signs 

-can be asymptomatic 

-Weakness, apathy, listlessness, bone pain, proximal muscle weakness

-spasms, convulsions, thickened and widened wrists and ankles 

-Craniotabes: thinning of the bones of the skull, soft, misshapen head, widened sutures, frontal bossing, muscle hypotonia, pronounced potbelly, bowing of the legs, waddling gait  

-Delayed eruption of teeth, pitted teeth 

-Rachitic rosary: Enlargement and cupping of the costochondral junctions resulting in widening of the chest 

-Genu Valgum: ‘Knock knees’ 

-Genu Varum: ‘Bowed legs’ 

-Harrison Groove: Tug of the diaphragm against the softened lower ribs may produce an indentation at the point of insertion of the diaphragm

Kyphoscoliosis or lumbar lordosis is common

-Hypocalcemia: fatigue,lethargy, irritability, depression, paresthesias in the circumoral area, muscle cramps, carpopedal spasm, convulsions, tetany, laryngospasm, and stridor 

-Hypophosphatemia: muscle weakness, reduced endurance, dysphagia, diplopia, cardiomyopathy, respiratory muscle weakness and impaired cognition

Diagnosis 

Histology: Transcortical bone biopsy 

Radiographs: bilateral bowing deformity of the femora, metaphyseal flaring, physeal widening 

Treatment 

-vitamin D